The business and culture of our digital lives, from the L.A. Times

Andy Rubin, the guy who runs Google's Android software unit, Monday night showed off a Motorola prototype tablet powered by an upcoming version of the mobile operating system dubbed Honeycomb made to run on tablets.

In an appearance at the All Things Digital's Dive Into Mobile conference in San Francisco, he showed off new 3-D features in Google Maps, using gestures to zoom in and tilt a map of San Francisco and showing buildings from different angles and a bird's-eye view.

The tablet will likely not be available until sometime next year. Rubin said tablets and the way people interact with them represent a fundamental shift in the evolution of computers.

"With the tablet, we're in the middle of one of those hockey sticks of evolution," he said.

When All Things D's Kara Swisher pressed Rubin to estimate how much the tablet would cost, he wouldn't say. The one in his hands, he quipped, would cost $10,000.

Rubin made the appearance hours after Google unveiled its Nexus S smartphone powered by a new version of android dubbed Gingerbread. The Nexus S follows the demise of the Nexus One, released in January and discontinued over the summer. Google sold the phone directly to consumers through a Google Web store, figuring people would buy phones the way they do other electronics rather than...

...through carriers. With more than 150 carriers worldwide, Rubin acknowledged that Google bit off more than it could chew trying to provision unlocked phones to work on different carriers. So Google decided to focus on the Android software.

"It was a scale issue," he said. "It was going to take literally three months to do every carrier."

The new Nexus S supports so-called near-field communications technology which could be used to create mobile payment applications so consumers could use their phones like digital wallets.

There are now more than 172 different phones running Android available around the world, Rubin said.

Under persistent questioning from Swisher and her colleague Walt Mossberg, Rubin also revealed that the Android mobile business would be profitable if it was a standalone company fueled by Google's mega advertising machine that sells ads alongside search results and places ads in mobile applications. Rubin joined Google when the Internet search giant bought his tiny mobile software startup. Android is designed to help Google’s Internet search, maps and other popular services make the leap from the desktop to mobile devices and challenge its arch rival Apple Inc.

"I probably wouldn't have made it as a separate company," Rubin said.

Google said in October that its mobile business had hit a $1-billion annualized revenue run rate.

Rubin also complimented Apple, where he used to work. He praised Apple's apps store for being "pretty open." He also said he expects Apple will find new opportunities as it pushes beyond selling devices into offering services such as selling books through its online store.

He would not answer questions about whether Research in Motion and Nokia might adopt Android. "You don't need to be a partner of Google to run Android," he said.

Android, the No. 3 mobile operating system in the U.S. as of October, is catching up to Apple and RIM, which makes the BlackBerry, reports research firm ComScore Inc.

The competitive edge for Google in its mobile efforts? Its origins as a startup giving it freedom from "legacy," he said.